We will estimate costs of occupational injury and illness using current data and improved methods. Costs will be estimated in the following categories: 1) economic categories of direct (medical, administrative) and indirect (lost earnings, fringe benefits, home production, employer costs); 2) demographic categories involving gender, race, ethnic, and age groups, as well as occupations, industries and states; 3) fatal diseases such as asthma, COPD, pneumoconiosis, bladder cancer, lung cancer, coronary heart disease, and renal disease; 4) non-fatal diseases such as dermatitis, carpal tunnel syndrome, hernia, and poisoning; 5) fatal injuries such as homicides and falls; 6) and non-fatal injuries such as amputations, bums, concussions, electric shock, fractures, sprains and strains. We will also conduct an extensive sensitivity analysis to determine how our estimates vary as key assumptions are altered. Fatal disease costs will be estimated by aggregating and cross-classifying data from government surveys, data sets, and reports. We will assign population-attributable risk percents (PAR%) based upon numerous studies that estimate the contribution of occupational exposures to the development of 19 fatal diseases. Indirect morbidity costs will be based on combining regression analyses of work-loss days, restricted activity days and bed days in the National Health Interview Survey with data on earnings (from the Bureau of Labor Statistics (BLS)) and home production. Indirect mortality Costs will use the Biddle model which includes medical cost data from the National Council on Compensation Insurance (NCCI) and a present value equation to estimate lost future earnings and home production. The BLS Annual Survey, adjusted for omissions of government workers and the self-employed as well as under-reporting, will be used to estimate non-fatal injuries and illnesses. Medical and indemnity data from the NCCI will be combined with wage-replacement rates to estimate costs in Workers' Compensation (WC) categories: medical only, temporary partial and total disability, permanent partial disability, and permanent total disability. The Biddle model will be used for fatal injuries. To forecast future costs we will combine our current cost estimates across occupations and industries with BLS 10-year projections for future employment in occupations and industries. An over-riding concern will be transparency. We will explain how estimates are derived and fully disclose all limitations. Another concern will be timeliness. The most recent study dates from 1992. But reported national injury rates have been fallen since 1992. Moreover, Workers' Compensation costs fell from 1993 to 1998 but have risen since 1999. Current and comprehensive estimates are needed.